Antimycotic activity of a methanolic extract from Azadirachta indica A Juss

Extracts of ground neem kernels were prepared by Soxhlet extraction with different organic solvents and with increasing polarity. After evaporation of the solvents, the residues were reconstituted in water and tested for their activity against phytopathogenic fungi. Tests were carried out by mixing pasteurized extracts into an agar medium, followed by incubation with fungal mycelium. The strongest growth inhibition was obtained with a methanolic extract. Further purification of the crude methanolic extract was carried out by liquid/liquid extraction and low-pressure column chromatography. The purity of the fractions was controlled by HPLC analysis and their activity subsequently tested. By using semipreparative HPLC the fungicidal activity of the extract was attributed to a single component. The structure of this component has to be elucidated.